Apart from GPS tracking for sports, multisports or basically any activity. Apart from being a smart watch where I have my phone on silent all the time and the clock is the only way of me reacting to notifications. I have a constant monitor over my vitals, it monitors my sleep, my recovery times, my body battery my pulse oximetry.
Add to that on top of my head, barometer, thermometer, compass altimeter etc.
And it is not a plastic watch, this one I have in titanium and sapphire glass if we want to talk durability.